POS0718 IS IT POSSIBLE TO EVALUATE POLYMYALGIA RHEUMATICA WITHOUT CRP? CONCORDANCE AND AGREEMENT BETWEEN DIFFERENT PMR-AS ACTIVITY SCORES IN POLYMYALGIA RHEUMATICA
Authors: D. Justine, S. Aghiles, A. Lohse, G. Carvajal Alegria, E. Dernis, C. Richez, M. E. Truchetet, D. Wendling, E. Toussirot, A. Perdriger, J. E. Gottenberg, B. Fautrel, L. Chiche, P. Hilliquin, C. Le Henaff Bourhis, D. Benjamin, G. Direz, I. Chary Valckenaere, D. Cornec, D. Guellec, T. Marhadour, N. Emmanuel, A. Saraux, V. Devauchelle-Pensec
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> The main treatment of polymyalgia rheumatica (PMR) is based on corticosteroid, but sparing agents are a major unmet need and many new treatments are evaluated to avoid corticosteroid side effects in PMR. To monitor the disease, one disease activity score has been developed specifically for polymyalgia rheumatica (PMR), the PMR-AS (activity score) also called CRP-PMR-AS. It is a composite index built as an algebraic sum of morning stiffness, elevation of the upper limbs, physician's global assessment, patient's pain assessment and the C reactive protein (CRP). However, treatments of PM such as IL-6 antagonists or corticosteroid can normalize CRP level. Derived PMR-AS have been described to avoid such bias: erythrocyte sedimentation rate (ESR) PMR-AS, Clinical PMR-AS and CRP-imputed PMR-AS but the concordance and the correlation between these scores are unknown. <h3>Objectives</h3> Our primary objective was to measure the correlation and concordance of the PMR-AS and the other activity scores and our secondary objective was to evaluate the weight of CRP in the PMR-AS. <h3>Methods</h3> The SEMAPHORE trial (Safety and Efficacy of tocilizumab versus Placebo in Polymyalgia rHeumatica with glucocORticoid dEpendence), a superiority randomized double-blind parallel placebo-controlled trial in patients with active PMR despite corticosteroid treatment, investigated whether tocilizumab resulted in higher rates of low disease activity compared to a placebo, after 24 weeks. Four different PMR-AS have been measured. Using kappa coefficient, intra class correlation coefficient, scatter plots and Bland Altman graphics, we evaluated the concordance and correlation between CRP-PMR-AS, ESR PMR-AS, Clinical PMR-AS and imp-CRP PMR-AS across the entire population and by treatment group (placebo versus Tocilizumab) for different cut offs (1.5; 7; 10; 17) at each visit (inclusion, week 4, 8, 12, 16, 20 and 24). <h3>Results</h3> 100 patients received at least one dose of tocilizumab (49 patients) or placebo (51 patients) and were included in the analyses from inclusion to week 24. The correlation between the different PMR activity scores were excellent in the global analysis (Figure 1) but also in the two groups of treatment. Intraclass coefficients were all higher than 0.9 (Table 1). Bland Altman graphics using PMR-AS as a reference showed that differences between scores are low regardless of PMR-AS. Kappa coefficients between CRP-PMR-AS and the other three scores showed a good agreement (&gt;0.8) (Table 1) at week 24. <h3>Conclusion</h3> The correlation between different PMR activity scores using or not CRP are excellent reflecting the low weight of CRP in the baseline composite index. In clinical trial using drugs that have an impact on CRP, CRP-PMR-AS or others, including clinical PMR-AS, can be used. <h3>REFERENCES:</h3> NIL. <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> D'AGOSTINO Justine: None declared, Souki Aghiles: None declared, Anne Lohse: None declared, Guillermo CARVAJAL ALEGRIA: None declared, Emmanuelle Dernis: None declared, Christophe Richez: None declared, Marie-Elise Truchetet: None declared, Daniel Wendling: None declared, ERIC TOUSSIROT: None declared, Aleth Perdriger: None declared, Jacques-Eric Gottenberg: None declared, Bruno Fautrel: None declared, Laurent Chiche: None declared, Pascal Hilliquin: None declared, CATHERINE LE HENAFF BOURHIS: None declared, Dervieux Benjamin: None declared, Guillaume DIREZ: None declared, Isabelle CHARY VALCKENAERE: None declared, Divi Cornec: None declared, Dewi Guellec: None declared, THIERRY MARHADOUR: None declared, Nowak Emmanuel: None declared, Alain Saraux: None declared, Valerie Devauchelle-Pensec Grant/research support from: Roche Chugai.